I sold something for way less than it’s worth

So I haven’t shipped the item yet. Would I be a bad person if I refund them and list it for higher? I’m not a reseller, I’m just selling most of what’s in my closet, because I’m so broke rn!! I sold an item for wayyyy less than it’s worth, because I didn’t actually know what to price it at, even after looking it up and using google lens. The person I sold it to is a reseller judging by their page, and I have nothing against resellers I promise!! I’ve bought a lot from resellers!! And that’s where a got a lot of my wardrobe!! But I could really use the extra money rn, I really do feel like I would be wrong of me. I’m not sure what to do.